Preparation and Thermal Analysis of Dicyclohexano-18-crown-6 Based Ternary Ionic Liquids (TILs)
Mentor 1
Mark Dietz
Location
Union Wisconsin Room
Start Date
24-4-2015 2:30 PM
End Date
24-4-2015 3:45 PM
Description
For more than a decade, ionic liquids (ILs) have been the object of intense interest as potential “green” replacements for the toxic and volatile organic solvents employed in a variety of electrochemical, catalytic, and separation processes. Recently a new class of ILs, known as ternary ionic liquids (TILs), has been described. Unlike “conventional” ILs, which typically comprise a bulky, asymmetric organic cation in combination with any of a wide variety of anions, TILs comprise a neutral ligand (e.g., a macrocyclic polyether), a cation bound by the ligand, and an appropriate counter anion. In an effort to develop principles to guide the design of new TILs, a systematic evaluation of the effect of the properties of the components on the characteristics of the resultant ionic liquid has been carried out. In addition, new synthetic methodology has been developed to provide TILs in higher yield and purity. In all, twelve new polyether-based ionic liquids have been prepared and their thermal properties (i.e., thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC)) determined. The results indicate that polyether stereoisomerism has a direct effect on both the melting point and the onset temperature of mass loss for the TIL. Also, as the size of the counter anion increases, the melting point of the ionic liquid decreases. In addition, the strength of metal-polyether complex formation appears to play a role in determining the thermal behavior of the TILs. These results represent an important first step toward the goal of developing predictive capabilities for ionic liquid design and eventually, tailoring the properties of an ionic liquid to its intended application.
Preparation and Thermal Analysis of Dicyclohexano-18-crown-6 Based Ternary Ionic Liquids (TILs)
Union Wisconsin Room
For more than a decade, ionic liquids (ILs) have been the object of intense interest as potential “green” replacements for the toxic and volatile organic solvents employed in a variety of electrochemical, catalytic, and separation processes. Recently a new class of ILs, known as ternary ionic liquids (TILs), has been described. Unlike “conventional” ILs, which typically comprise a bulky, asymmetric organic cation in combination with any of a wide variety of anions, TILs comprise a neutral ligand (e.g., a macrocyclic polyether), a cation bound by the ligand, and an appropriate counter anion. In an effort to develop principles to guide the design of new TILs, a systematic evaluation of the effect of the properties of the components on the characteristics of the resultant ionic liquid has been carried out. In addition, new synthetic methodology has been developed to provide TILs in higher yield and purity. In all, twelve new polyether-based ionic liquids have been prepared and their thermal properties (i.e., thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC)) determined. The results indicate that polyether stereoisomerism has a direct effect on both the melting point and the onset temperature of mass loss for the TIL. Also, as the size of the counter anion increases, the melting point of the ionic liquid decreases. In addition, the strength of metal-polyether complex formation appears to play a role in determining the thermal behavior of the TILs. These results represent an important first step toward the goal of developing predictive capabilities for ionic liquid design and eventually, tailoring the properties of an ionic liquid to its intended application.
